/lib/dml/pgsql_native_moodle_database.php
PHP | 1343 lines | 1004 code | 118 blank | 221 comment | 100 complexity | cadb3d6eea6dc5d463b7e49f8ec6ebce MD5 | raw file
- <?php
- // This file is part of Moodle - http://moodle.org/
- //
- // Moodle is free software: you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation, either version 3 of the License, or
- // (at your option) any later version.
- //
- // Moodle is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
- /**
- * Native pgsql class representing moodle database interface.
- *
- * @package core_dml
- * @copyright 2008 Petr Skoda (http://skodak.org)
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- defined('MOODLE_INTERNAL') || die();
- require_once(__DIR__.'/moodle_database.php');
- require_once(__DIR__.'/pgsql_native_moodle_recordset.php');
- require_once(__DIR__.'/pgsql_native_moodle_temptables.php');
- /**
- * Native pgsql class representing moodle database interface.
- *
- * @package core_dml
- * @copyright 2008 Petr Skoda (http://skodak.org)
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class pgsql_native_moodle_database extends moodle_database {
- protected $pgsql = null;
- protected $bytea_oid = null;
- protected $last_error_reporting; // To handle pgsql driver default verbosity
- /** @var bool savepoint hack for MDL-35506 - workaround for automatic transaction rollback on error */
- protected $savepointpresent = false;
- /**
- * Detects if all needed PHP stuff installed.
- * Note: can be used before connect()
- * @return mixed true if ok, string if something
- */
- public function driver_installed() {
- if (!extension_loaded('pgsql')) {
- return get_string('pgsqlextensionisnotpresentinphp', 'install');
- }
- return true;
- }
- /**
- * Returns database family type - describes SQL dialect
- * Note: can be used before connect()
- * @return string db family name (mysql, postgres, mssql, oracle, etc.)
- */
- public function get_dbfamily() {
- return 'postgres';
- }
- /**
- * Returns more specific database driver type
- * Note: can be used before connect()
- * @return string db type mysqli, pgsql, oci, mssql, sqlsrv
- */
- protected function get_dbtype() {
- return 'pgsql';
- }
- /**
- * Returns general database library name
- * Note: can be used before connect()
- * @return string db type pdo, native
- */
- protected function get_dblibrary() {
- return 'native';
- }
- /**
- * Returns localised database type name
- * Note: can be used before connect()
- * @return string
- */
- public function get_name() {
- return get_string('nativepgsql', 'install');
- }
- /**
- * Returns localised database configuration help.
- * Note: can be used before connect()
- * @return string
- */
- public function get_configuration_help() {
- return get_string('nativepgsqlhelp', 'install');
- }
- /**
- * Returns localised database description
- * Note: can be used before connect()
- * @return string
- */
- public function get_configuration_hints() {
- return get_string('databasesettingssub_postgres7', 'install');
- }
- /**
- * Connect to db
- * Must be called before other methods.
- * @param string $dbhost The database host.
- * @param string $dbuser The database username.
- * @param string $dbpass The database username's password.
- * @param string $dbname The name of the database being connected to.
- * @param mixed $prefix string means moodle db prefix, false used for external databases where prefix not used
- * @param array $dboptions driver specific options
- * @return bool true
- * @throws dml_connection_exception if error
- */
- public function connect($dbhost, $dbuser, $dbpass, $dbname, $prefix, array $dboptions=null) {
- if ($prefix == '' and !$this->external) {
- //Enforce prefixes for everybody but mysql
- throw new dml_exception('prefixcannotbeempty', $this->get_dbfamily());
- }
- $driverstatus = $this->driver_installed();
- if ($driverstatus !== true) {
- throw new dml_exception('dbdriverproblem', $driverstatus);
- }
- $this->store_settings($dbhost, $dbuser, $dbpass, $dbname, $prefix, $dboptions);
- $pass = addcslashes($this->dbpass, "'\\");
- // Unix socket connections should have lower overhead
- if (!empty($this->dboptions['dbsocket']) and ($this->dbhost === 'localhost' or $this->dbhost === '127.0.0.1')) {
- $connection = "user='$this->dbuser' password='$pass' dbname='$this->dbname'";
- if (strpos($this->dboptions['dbsocket'], '/') !== false) {
- $connection = $connection." host='".$this->dboptions['dbsocket']."'";
- }
- } else {
- $this->dboptions['dbsocket'] = '';
- if (empty($this->dbname)) {
- // probably old style socket connection - do not add port
- $port = "";
- } else if (empty($this->dboptions['dbport'])) {
- $port = "port ='5432'";
- } else {
- $port = "port ='".$this->dboptions['dbport']."'";
- }
- $connection = "host='$this->dbhost' $port user='$this->dbuser' password='$pass' dbname='$this->dbname'";
- }
- ob_start();
- if (empty($this->dboptions['dbpersist'])) {
- $this->pgsql = pg_connect($connection, PGSQL_CONNECT_FORCE_NEW);
- } else {
- $this->pgsql = pg_pconnect($connection, PGSQL_CONNECT_FORCE_NEW);
- }
- $dberr = ob_get_contents();
- ob_end_clean();
- $status = pg_connection_status($this->pgsql);
- if ($status === false or $status === PGSQL_CONNECTION_BAD) {
- $this->pgsql = null;
- throw new dml_connection_exception($dberr);
- }
- $this->query_start("--pg_set_client_encoding()", null, SQL_QUERY_AUX);
- pg_set_client_encoding($this->pgsql, 'utf8');
- $this->query_end(true);
- $sql = '';
- // Only for 9.0 and upwards, set bytea encoding to old format.
- if ($this->is_min_version('9.0')) {
- $sql = "SET bytea_output = 'escape'; ";
- }
- // Select schema if specified, otherwise the first one wins.
- if (!empty($this->dboptions['dbschema'])) {
- $sql .= "SET search_path = '".$this->dboptions['dbschema']."'; ";
- }
- // Find out the bytea oid.
- $sql .= "SELECT oid FROM pg_type WHERE typname = 'bytea'";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- $this->bytea_oid = pg_fetch_result($result, 0, 0);
- pg_free_result($result);
- if ($this->bytea_oid === false) {
- $this->pgsql = null;
- throw new dml_connection_exception('Can not read bytea type.');
- }
- // Connection stabilised and configured, going to instantiate the temptables controller
- $this->temptables = new pgsql_native_moodle_temptables($this);
- return true;
- }
- /**
- * Close database connection and release all resources
- * and memory (especially circular memory references).
- * Do NOT use connect() again, create a new instance if needed.
- */
- public function dispose() {
- parent::dispose(); // Call parent dispose to write/close session and other common stuff before closing connection
- if ($this->pgsql) {
- pg_close($this->pgsql);
- $this->pgsql = null;
- }
- }
- /**
- * Called before each db query.
- * @param string $sql
- * @param array array of parameters
- * @param int $type type of query
- * @param mixed $extrainfo driver specific extra information
- * @return void
- */
- protected function query_start($sql, array $params=null, $type, $extrainfo=null) {
- parent::query_start($sql, $params, $type, $extrainfo);
- // pgsql driver tents to send debug to output, we do not need that ;-)
- $this->last_error_reporting = error_reporting(0);
- }
- /**
- * Called immediately after each db query.
- * @param mixed db specific result
- * @return void
- */
- protected function query_end($result) {
- // reset original debug level
- error_reporting($this->last_error_reporting);
- try {
- parent::query_end($result);
- if ($this->savepointpresent and $this->last_type != SQL_QUERY_AUX and $this->last_type != SQL_QUERY_SELECT) {
- $res = @pg_query($this->pgsql, "RELEASE SAVEPOINT moodle_pg_savepoint; SAVEPOINT moodle_pg_savepoint");
- if ($res) {
- pg_free_result($res);
- }
- }
- } catch (Exception $e) {
- if ($this->savepointpresent) {
- $res = @pg_query($this->pgsql, "ROLLBACK TO SAVEPOINT moodle_pg_savepoint; SAVEPOINT moodle_pg_savepoint");
- if ($res) {
- pg_free_result($res);
- }
- }
- throw $e;
- }
- }
- /**
- * Returns database server info array
- * @return array Array containing 'description' and 'version' info
- */
- public function get_server_info() {
- static $info;
- if (!$info) {
- $this->query_start("--pg_version()", null, SQL_QUERY_AUX);
- $info = pg_version($this->pgsql);
- $this->query_end(true);
- }
- return array('description'=>$info['server'], 'version'=>$info['server']);
- }
- /**
- * Returns if the RDBMS server fulfills the required version
- *
- * @param string $version version to check against
- * @return bool returns if the version is fulfilled (true) or no (false)
- */
- private function is_min_version($version) {
- $server = $this->get_server_info();
- $server = $server['version'];
- return version_compare($server, $version, '>=');
- }
- /**
- * Returns supported query parameter types
- * @return int bitmask of accepted SQL_PARAMS_*
- */
- protected function allowed_param_types() {
- return SQL_PARAMS_DOLLAR;
- }
- /**
- * Returns last error reported by database engine.
- * @return string error message
- */
- public function get_last_error() {
- return pg_last_error($this->pgsql);
- }
- /**
- * Return tables in database WITHOUT current prefix.
- * @param bool $usecache if true, returns list of cached tables.
- * @return array of table names in lowercase and without prefix
- */
- public function get_tables($usecache=true) {
- if ($usecache and $this->tables !== null) {
- return $this->tables;
- }
- $this->tables = array();
- $prefix = str_replace('_', '|_', $this->prefix);
- $sql = "SELECT c.relname
- FROM pg_catalog.pg_class c
- JOIN pg_catalog.pg_namespace as ns ON ns.oid = c.relnamespace
- WHERE c.relname LIKE '$prefix%' ESCAPE '|'
- AND c.relkind = 'r'
- AND (ns.nspname = current_schema() OR ns.oid = pg_my_temp_schema())";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result) {
- while ($row = pg_fetch_row($result)) {
- $tablename = reset($row);
- if ($this->prefix !== '') {
- if (strpos($tablename, $this->prefix) !== 0) {
- continue;
- }
- $tablename = substr($tablename, strlen($this->prefix));
- }
- $this->tables[$tablename] = $tablename;
- }
- pg_free_result($result);
- }
- return $this->tables;
- }
- /**
- * Return table indexes - everything lowercased.
- * @param string $table The table we want to get indexes from.
- * @return array of arrays
- */
- public function get_indexes($table) {
- $indexes = array();
- $tablename = $this->prefix.$table;
- $sql = "SELECT i.*
- FROM pg_catalog.pg_indexes i
- JOIN pg_catalog.pg_namespace as ns ON ns.nspname = i.schemaname
- WHERE i.tablename = '$tablename'
- AND (i.schemaname = current_schema() OR ns.oid = pg_my_temp_schema())";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result) {
- while ($row = pg_fetch_assoc($result)) {
- if (!preg_match('/CREATE (|UNIQUE )INDEX ([^\s]+) ON '.$tablename.' USING ([^\s]+) \(([^\)]+)\)/i', $row['indexdef'], $matches)) {
- continue;
- }
- if ($matches[4] === 'id') {
- continue;
- }
- $columns = explode(',', $matches[4]);
- foreach ($columns as $k=>$column) {
- $column = trim($column);
- if ($pos = strpos($column, ' ')) {
- // index type is separated by space
- $column = substr($column, 0, $pos);
- }
- $columns[$k] = $this->trim_quotes($column);
- }
- $indexes[$row['indexname']] = array('unique'=>!empty($matches[1]),
- 'columns'=>$columns);
- }
- pg_free_result($result);
- }
- return $indexes;
- }
- /**
- * Returns detailed information about columns in table. This information is cached internally.
- * @param string $table name
- * @param bool $usecache
- * @return array array of database_column_info objects indexed with column names
- */
- public function get_columns($table, $usecache=true) {
- if ($usecache) {
- $properties = array('dbfamily' => $this->get_dbfamily(), 'settings' => $this->get_settings_hash());
- $cache = cache::make('core', 'databasemeta', $properties);
- if ($data = $cache->get($table)) {
- return $data;
- }
- }
- $structure = array();
- $tablename = $this->prefix.$table;
- $sql = "SELECT a.attnum, a.attname AS field, t.typname AS type, a.attlen, a.atttypmod, a.attnotnull, a.atthasdef, d.adsrc
- FROM pg_catalog.pg_class c
- JOIN pg_catalog.pg_namespace as ns ON ns.oid = c.relnamespace
- JOIN pg_catalog.pg_attribute a ON a.attrelid = c.oid
- JOIN pg_catalog.pg_type t ON t.oid = a.atttypid
- LEFT JOIN pg_catalog.pg_attrdef d ON (d.adrelid = c.oid AND d.adnum = a.attnum)
- WHERE relkind = 'r' AND c.relname = '$tablename' AND c.reltype > 0 AND a.attnum > 0
- AND (ns.nspname = current_schema() OR ns.oid = pg_my_temp_schema())
- ORDER BY a.attnum";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if (!$result) {
- return array();
- }
- while ($rawcolumn = pg_fetch_object($result)) {
- $info = new stdClass();
- $info->name = $rawcolumn->field;
- $matches = null;
- if ($rawcolumn->type === 'varchar') {
- $info->type = 'varchar';
- $info->meta_type = 'C';
- $info->max_length = $rawcolumn->atttypmod - 4;
- $info->scale = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- $info->has_default = ($rawcolumn->atthasdef === 't');
- if ($info->has_default) {
- $parts = explode('::', $rawcolumn->adsrc);
- if (count($parts) > 1) {
- $info->default_value = reset($parts);
- $info->default_value = trim($info->default_value, "'");
- } else {
- $info->default_value = $rawcolumn->adsrc;
- }
- } else {
- $info->default_value = null;
- }
- $info->primary_key = false;
- $info->binary = false;
- $info->unsigned = null;
- $info->auto_increment= false;
- $info->unique = null;
- } else if (preg_match('/int(\d)/i', $rawcolumn->type, $matches)) {
- $info->type = 'int';
- if (strpos($rawcolumn->adsrc, 'nextval') === 0) {
- $info->primary_key = true;
- $info->meta_type = 'R';
- $info->unique = true;
- $info->auto_increment= true;
- $info->has_default = false;
- } else {
- $info->primary_key = false;
- $info->meta_type = 'I';
- $info->unique = null;
- $info->auto_increment= false;
- $info->has_default = ($rawcolumn->atthasdef === 't');
- }
- // Return number of decimals, not bytes here.
- if ($matches[1] >= 8) {
- $info->max_length = 18;
- } else if ($matches[1] >= 4) {
- $info->max_length = 9;
- } else if ($matches[1] >= 2) {
- $info->max_length = 4;
- } else if ($matches[1] >= 1) {
- $info->max_length = 2;
- } else {
- $info->max_length = 0;
- }
- $info->scale = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- if ($info->has_default) {
- $info->default_value = trim($rawcolumn->adsrc, '()');
- } else {
- $info->default_value = null;
- }
- $info->binary = false;
- $info->unsigned = false;
- } else if ($rawcolumn->type === 'numeric') {
- $info->type = $rawcolumn->type;
- $info->meta_type = 'N';
- $info->primary_key = false;
- $info->binary = false;
- $info->unsigned = null;
- $info->auto_increment= false;
- $info->unique = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- $info->has_default = ($rawcolumn->atthasdef === 't');
- if ($info->has_default) {
- $info->default_value = trim($rawcolumn->adsrc, '()');
- } else {
- $info->default_value = null;
- }
- $info->max_length = $rawcolumn->atttypmod >> 16;
- $info->scale = ($rawcolumn->atttypmod & 0xFFFF) - 4;
- } else if (preg_match('/float(\d)/i', $rawcolumn->type, $matches)) {
- $info->type = 'float';
- $info->meta_type = 'N';
- $info->primary_key = false;
- $info->binary = false;
- $info->unsigned = null;
- $info->auto_increment= false;
- $info->unique = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- $info->has_default = ($rawcolumn->atthasdef === 't');
- if ($info->has_default) {
- $info->default_value = trim($rawcolumn->adsrc, '()');
- } else {
- $info->default_value = null;
- }
- // just guess expected number of deciaml places :-(
- if ($matches[1] == 8) {
- // total 15 digits
- $info->max_length = 8;
- $info->scale = 7;
- } else {
- // total 6 digits
- $info->max_length = 4;
- $info->scale = 2;
- }
- } else if ($rawcolumn->type === 'text') {
- $info->type = $rawcolumn->type;
- $info->meta_type = 'X';
- $info->max_length = -1;
- $info->scale = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- $info->has_default = ($rawcolumn->atthasdef === 't');
- if ($info->has_default) {
- $parts = explode('::', $rawcolumn->adsrc);
- if (count($parts) > 1) {
- $info->default_value = reset($parts);
- $info->default_value = trim($info->default_value, "'");
- } else {
- $info->default_value = $rawcolumn->adsrc;
- }
- } else {
- $info->default_value = null;
- }
- $info->primary_key = false;
- $info->binary = false;
- $info->unsigned = null;
- $info->auto_increment= false;
- $info->unique = null;
- } else if ($rawcolumn->type === 'bytea') {
- $info->type = $rawcolumn->type;
- $info->meta_type = 'B';
- $info->max_length = -1;
- $info->scale = null;
- $info->not_null = ($rawcolumn->attnotnull === 't');
- $info->has_default = false;
- $info->default_value = null;
- $info->primary_key = false;
- $info->binary = true;
- $info->unsigned = null;
- $info->auto_increment= false;
- $info->unique = null;
- }
- $structure[$info->name] = new database_column_info($info);
- }
- pg_free_result($result);
- if ($usecache) {
- $result = $cache->set($table, $structure);
- }
- return $structure;
- }
- /**
- * Normalise values based in RDBMS dependencies (booleans, LOBs...)
- *
- * @param database_column_info $column column metadata corresponding with the value we are going to normalise
- * @param mixed $value value we are going to normalise
- * @return mixed the normalised value
- */
- protected function normalise_value($column, $value) {
- $this->detect_objects($value);
- if (is_bool($value)) { // Always, convert boolean to int
- $value = (int)$value;
- } else if ($column->meta_type === 'B') { // BLOB detected, we return 'blob' array instead of raw value to allow
- if (!is_null($value)) { // binding/executing code later to know about its nature
- $value = array('blob' => $value);
- }
- } else if ($value === '') {
- if ($column->meta_type === 'I' or $column->meta_type === 'F' or $column->meta_type === 'N') {
- $value = 0; // prevent '' problems in numeric fields
- }
- }
- return $value;
- }
- /**
- * Is db in unicode mode?
- * @return bool
- */
- public function setup_is_unicodedb() {
- // Get PostgreSQL server_encoding value
- $sql = "SHOW server_encoding";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if (!$result) {
- return false;
- }
- $rawcolumn = pg_fetch_object($result);
- $encoding = $rawcolumn->server_encoding;
- pg_free_result($result);
- return (strtoupper($encoding) == 'UNICODE' || strtoupper($encoding) == 'UTF8');
- }
- /**
- * Do NOT use in code, to be used by database_manager only!
- * @param string $sql query
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function change_database_structure($sql) {
- $this->reset_caches();
- $this->query_start($sql, null, SQL_QUERY_STRUCTURE);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- /**
- * Execute general sql query. Should be used only when no other method suitable.
- * Do NOT use this to make changes in db structure, use database_manager methods instead!
- * @param string $sql query
- * @param array $params query parameters
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function execute($sql, array $params=null) {
- list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
- if (strpos($sql, ';') !== false) {
- throw new coding_exception('moodle_database::execute() Multiple sql statements found or bound parameters not used properly in query!');
- }
- $this->query_start($sql, $params, SQL_QUERY_UPDATE);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- /**
- * Get a number of records as a moodle_recordset using a SQL statement.
- *
- * Since this method is a little less readable, use of it should be restricted to
- * code where it's possible there might be large datasets being returned. For known
- * small datasets use get_records_sql - it leads to simpler code.
- *
- * The return type is like:
- * @see function get_recordset.
- *
- * @param string $sql the SQL select query to execute.
- * @param array $params array of sql parameters
- * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
- * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
- * @return moodle_recordset instance
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function get_recordset_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
- $limitfrom = (int)$limitfrom;
- $limitnum = (int)$limitnum;
- $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
- $limitnum = ($limitnum < 0) ? 0 : $limitnum;
- if ($limitfrom or $limitnum) {
- if ($limitnum < 1) {
- $limitnum = "ALL";
- } else if (PHP_INT_MAX - $limitnum < $limitfrom) {
- // this is a workaround for weird max int problem
- $limitnum = "ALL";
- }
- $sql .= " LIMIT $limitnum OFFSET $limitfrom";
- }
- list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
- $this->query_start($sql, $params, SQL_QUERY_SELECT);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- return $this->create_recordset($result);
- }
- protected function create_recordset($result) {
- return new pgsql_native_moodle_recordset($result, $this->bytea_oid);
- }
- /**
- * Get a number of records as an array of objects using a SQL statement.
- *
- * Return value is like:
- * @see function get_records.
- *
- * @param string $sql the SQL select query to execute. The first column of this SELECT statement
- * must be a unique value (usually the 'id' field), as it will be used as the key of the
- * returned array.
- * @param array $params array of sql parameters
- * @param int $limitfrom return a subset of records, starting at this point (optional, required if $limitnum is set).
- * @param int $limitnum return a subset comprising this many records (optional, required if $limitfrom is set).
- * @return array of objects, or empty array if no records were found
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function get_records_sql($sql, array $params=null, $limitfrom=0, $limitnum=0) {
- $limitfrom = (int)$limitfrom;
- $limitnum = (int)$limitnum;
- $limitfrom = ($limitfrom < 0) ? 0 : $limitfrom;
- $limitnum = ($limitnum < 0) ? 0 : $limitnum;
- if ($limitfrom or $limitnum) {
- if ($limitnum < 1) {
- $limitnum = "ALL";
- } else if (PHP_INT_MAX - $limitnum < $limitfrom) {
- // this is a workaround for weird max int problem
- $limitnum = "ALL";
- }
- $sql .= " LIMIT $limitnum OFFSET $limitfrom";
- }
- list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
- $this->query_start($sql, $params, SQL_QUERY_SELECT);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- // find out if there are any blobs
- $numrows = pg_num_fields($result);
- $blobs = array();
- for($i=0; $i<$numrows; $i++) {
- $type_oid = pg_field_type_oid($result, $i);
- if ($type_oid == $this->bytea_oid) {
- $blobs[] = pg_field_name($result, $i);
- }
- }
- $rows = pg_fetch_all($result);
- pg_free_result($result);
- $return = array();
- if ($rows) {
- foreach ($rows as $row) {
- $id = reset($row);
- if ($blobs) {
- foreach ($blobs as $blob) {
- // note: in PostgreSQL 9.0 the returned blobs are hexencoded by default - see http://www.postgresql.org/docs/9.0/static/runtime-config-client.html#GUC-BYTEA-OUTPUT
- $row[$blob] = $row[$blob] !== null ? pg_unescape_bytea($row[$blob]) : null;
- }
- }
- if (isset($return[$id])) {
- $colname = key($row);
- debugging("Did you remember to make the first column something unique in your call to get_records? Duplicate value '$id' found in column '$colname'.", DEBUG_DEVELOPER);
- }
- $return[$id] = (object)$row;
- }
- }
- return $return;
- }
- /**
- * Selects records and return values (first field) as an array using a SQL statement.
- *
- * @param string $sql The SQL query
- * @param array $params array of sql parameters
- * @return array of values
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function get_fieldset_sql($sql, array $params=null) {
- list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
- $this->query_start($sql, $params, SQL_QUERY_SELECT);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- $return = pg_fetch_all_columns($result, 0);
- pg_free_result($result);
- return $return;
- }
- /**
- * Insert new record into database, as fast as possible, no safety checks, lobs not supported.
- * @param string $table name
- * @param mixed $params data record as object or array
- * @param bool $returnit return it of inserted record
- * @param bool $bulk true means repeated inserts expected
- * @param bool $customsequence true if 'id' included in $params, disables $returnid
- * @return bool|int true or new id
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function insert_record_raw($table, $params, $returnid=true, $bulk=false, $customsequence=false) {
- if (!is_array($params)) {
- $params = (array)$params;
- }
- $returning = "";
- if ($customsequence) {
- if (!isset($params['id'])) {
- throw new coding_exception('moodle_database::insert_record_raw() id field must be specified if custom sequences used.');
- }
- $returnid = false;
- } else {
- if ($returnid) {
- $returning = "RETURNING id";
- unset($params['id']);
- } else {
- unset($params['id']);
- }
- }
- if (empty($params)) {
- throw new coding_exception('moodle_database::insert_record_raw() no fields found.');
- }
- $fields = implode(',', array_keys($params));
- $values = array();
- $i = 1;
- foreach ($params as $value) {
- $this->detect_objects($value);
- $values[] = "\$".$i++;
- }
- $values = implode(',', $values);
- $sql = "INSERT INTO {$this->prefix}$table ($fields) VALUES($values) $returning";
- $this->query_start($sql, $params, SQL_QUERY_INSERT);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- if ($returning !== "") {
- $row = pg_fetch_assoc($result);
- $params['id'] = reset($row);
- }
- pg_free_result($result);
- if (!$returnid) {
- return true;
- }
- return (int)$params['id'];
- }
- /**
- * Insert a record into a table and return the "id" field if required.
- *
- * Some conversions and safety checks are carried out. Lobs are supported.
- * If the return ID isn't required, then this just reports success as true/false.
- * $data is an object containing needed data
- * @param string $table The database table to be inserted into
- * @param object $data A data object with values for one or more fields in the record
- * @param bool $returnid Should the id of the newly created record entry be returned? If this option is not requested then true/false is returned.
- * @return bool|int true or new id
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function insert_record($table, $dataobject, $returnid=true, $bulk=false) {
- $dataobject = (array)$dataobject;
- $columns = $this->get_columns($table);
- $cleaned = array();
- $blobs = array();
- foreach ($dataobject as $field=>$value) {
- if ($field === 'id') {
- continue;
- }
- if (!isset($columns[$field])) {
- continue;
- }
- $column = $columns[$field];
- $normalised_value = $this->normalise_value($column, $value);
- if (is_array($normalised_value) && array_key_exists('blob', $normalised_value)) {
- $cleaned[$field] = '@#BLOB#@';
- $blobs[$field] = $normalised_value['blob'];
- } else {
- $cleaned[$field] = $normalised_value;
- }
- }
- if (empty($blobs)) {
- return $this->insert_record_raw($table, $cleaned, $returnid, $bulk);
- }
- $id = $this->insert_record_raw($table, $cleaned, true, $bulk);
- foreach ($blobs as $key=>$value) {
- $value = pg_escape_bytea($this->pgsql, $value);
- $sql = "UPDATE {$this->prefix}$table SET $key = '$value'::bytea WHERE id = $id";
- $this->query_start($sql, NULL, SQL_QUERY_UPDATE);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result !== false) {
- pg_free_result($result);
- }
- }
- return ($returnid ? $id : true);
- }
- /**
- * Import a record into a table, id field is required.
- * Safety checks are NOT carried out. Lobs are supported.
- *
- * @param string $table name of database table to be inserted into
- * @param object $dataobject A data object with values for one or more fields in the record
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function import_record($table, $dataobject) {
- $dataobject = (array)$dataobject;
- $columns = $this->get_columns($table);
- $cleaned = array();
- $blobs = array();
- foreach ($dataobject as $field=>$value) {
- $this->detect_objects($value);
- if (!isset($columns[$field])) {
- continue;
- }
- if ($columns[$field]->meta_type === 'B') {
- if (!is_null($value)) {
- $cleaned[$field] = '@#BLOB#@';
- $blobs[$field] = $value;
- continue;
- }
- }
- $cleaned[$field] = $value;
- }
- $this->insert_record_raw($table, $cleaned, false, true, true);
- $id = $dataobject['id'];
- foreach ($blobs as $key=>$value) {
- $value = pg_escape_bytea($this->pgsql, $value);
- $sql = "UPDATE {$this->prefix}$table SET $key = '$value'::bytea WHERE id = $id";
- $this->query_start($sql, NULL, SQL_QUERY_UPDATE);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result !== false) {
- pg_free_result($result);
- }
- }
- return true;
- }
- /**
- * Update record in database, as fast as possible, no safety checks, lobs not supported.
- * @param string $table name
- * @param mixed $params data record as object or array
- * @param bool true means repeated updates expected
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function update_record_raw($table, $params, $bulk=false) {
- $params = (array)$params;
- if (!isset($params['id'])) {
- throw new coding_exception('moodle_database::update_record_raw() id field must be specified.');
- }
- $id = $params['id'];
- unset($params['id']);
- if (empty($params)) {
- throw new coding_exception('moodle_database::update_record_raw() no fields found.');
- }
- $i = 1;
- $sets = array();
- foreach ($params as $field=>$value) {
- $this->detect_objects($value);
- $sets[] = "$field = \$".$i++;
- }
- $params[] = $id; // last ? in WHERE condition
- $sets = implode(',', $sets);
- $sql = "UPDATE {$this->prefix}$table SET $sets WHERE id=\$".$i;
- $this->query_start($sql, $params, SQL_QUERY_UPDATE);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- /**
- * Update a record in a table
- *
- * $dataobject is an object containing needed data
- * Relies on $dataobject having a variable "id" to
- * specify the record to update
- *
- * @param string $table The database table to be checked against.
- * @param object $dataobject An object with contents equal to fieldname=>fieldvalue. Must have an entry for 'id' to map to the table specified.
- * @param bool true means repeated updates expected
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function update_record($table, $dataobject, $bulk=false) {
- $dataobject = (array)$dataobject;
- $columns = $this->get_columns($table);
- $cleaned = array();
- $blobs = array();
- foreach ($dataobject as $field=>$value) {
- if (!isset($columns[$field])) {
- continue;
- }
- $column = $columns[$field];
- $normalised_value = $this->normalise_value($column, $value);
- if (is_array($normalised_value) && array_key_exists('blob', $normalised_value)) {
- $cleaned[$field] = '@#BLOB#@';
- $blobs[$field] = $normalised_value['blob'];
- } else {
- $cleaned[$field] = $normalised_value;
- }
- }
- $this->update_record_raw($table, $cleaned, $bulk);
- if (empty($blobs)) {
- return true;
- }
- $id = (int)$dataobject['id'];
- foreach ($blobs as $key=>$value) {
- $value = pg_escape_bytea($this->pgsql, $value);
- $sql = "UPDATE {$this->prefix}$table SET $key = '$value'::bytea WHERE id = $id";
- $this->query_start($sql, NULL, SQL_QUERY_UPDATE);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- pg_free_result($result);
- }
- return true;
- }
- /**
- * Set a single field in every table record which match a particular WHERE clause.
- *
- * @param string $table The database table to be checked against.
- * @param string $newfield the field to set.
- * @param string $newvalue the value to set the field to.
- * @param string $select A fragment of SQL to be used in a where clause in the SQL call.
- * @param array $params array of sql parameters
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function set_field_select($table, $newfield, $newvalue, $select, array $params=null) {
- if ($select) {
- $select = "WHERE $select";
- }
- if (is_null($params)) {
- $params = array();
- }
- list($select, $params, $type) = $this->fix_sql_params($select, $params);
- $i = count($params)+1;
- // Get column metadata
- $columns = $this->get_columns($table);
- $column = $columns[$newfield];
- $normalised_value = $this->normalise_value($column, $newvalue);
- if (is_array($normalised_value) && array_key_exists('blob', $normalised_value)) {
- // Update BYTEA and return
- $normalised_value = pg_escape_bytea($this->pgsql, $normalised_value['blob']);
- $sql = "UPDATE {$this->prefix}$table SET $newfield = '$normalised_value'::bytea $select";
- $this->query_start($sql, NULL, SQL_QUERY_UPDATE);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- if (is_null($normalised_value)) {
- $newfield = "$newfield = NULL";
- } else {
- $newfield = "$newfield = \$".$i;
- $params[] = $normalised_value;
- }
- $sql = "UPDATE {$this->prefix}$table SET $newfield $select";
- $this->query_start($sql, $params, SQL_QUERY_UPDATE);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- /**
- * Delete one or more records from a table which match a particular WHERE clause.
- *
- * @param string $table The database table to be checked against.
- * @param string $select A fragment of SQL to be used in a where clause in the SQL call (used to define the selection criteria).
- * @param array $params array of sql parameters
- * @return bool true
- * @throws dml_exception A DML specific exception is thrown for any errors.
- */
- public function delete_records_select($table, $select, array $params=null) {
- if ($select) {
- $select = "WHERE $select";
- }
- $sql = "DELETE FROM {$this->prefix}$table $select";
- list($sql, $params, $type) = $this->fix_sql_params($sql, $params);
- $this->query_start($sql, $params, SQL_QUERY_UPDATE);
- $result = pg_query_params($this->pgsql, $sql, $params);
- $this->query_end($result);
- pg_free_result($result);
- return true;
- }
- /**
- * Returns 'LIKE' part of a query.
- *
- * @param string $fieldname usually name of the table column
- * @param string $param usually bound query parameter (?, :named)
- * @param bool $casesensitive use case sensitive search
- * @param bool $accensensitive use accent sensitive search (not all databases support accent insensitive)
- * @param bool $notlike true means "NOT LIKE"
- * @param string $escapechar escape char for '%' and '_'
- * @return string SQL code fragment
- */
- public function sql_like($fieldname, $param, $casesensitive = true, $accentsensitive = true, $notlike = false, $escapechar = '\\') {
- if (strpos($param, '%') !== false) {
- debugging('Potential SQL injection detected, sql_like() expects bound parameters (? or :named)');
- }
- if ($escapechar === '\\') {
- // Prevents problems with C-style escapes of enclosing '\',
- // E'... bellow prevents compatibility warnings.
- $escapechar = '\\\\';
- }
- // postgresql does not support accent insensitive text comparisons, sorry
- if ($casesensitive) {
- $LIKE = $notlike ? 'NOT LIKE' : 'LIKE';
- } else {
- $LIKE = $notlike ? 'NOT ILIKE' : 'ILIKE';
- }
- return "$fieldname $LIKE $param ESCAPE E'$escapechar'";
- }
- public function sql_bitxor($int1, $int2) {
- return '((' . $int1 . ') # (' . $int2 . '))';
- }
- public function sql_cast_char2int($fieldname, $text=false) {
- return ' CAST(' . $fieldname . ' AS INT) ';
- }
- public function sql_cast_char2real($fieldname, $text=false) {
- return " $fieldname::real ";
- }
- public function sql_concat() {
- $arr = func_get_args();
- $s = implode(' || ', $arr);
- if ($s === '') {
- return " '' ";
- }
- // Add always empty string element so integer-exclusive concats
- // will work without needing to cast each element explicitly
- return " '' || $s ";
- }
- public function sql_concat_join($separator="' '", $elements=array()) {
- for ($n=count($elements)-1; $n > 0 ; $n--) {
- array_splice($elements, $n, 0, $separator);
- }
- $s = implode(' || ', $elements);
- if ($s === '') {
- return " '' ";
- }
- return " $s ";
- }
- public function sql_regex_supported() {
- return true;
- }
- public function sql_regex($positivematch=true) {
- return $positivematch ? '~*' : '!~*';
- }
- public function session_lock_supported() {
- return true;
- }
- /**
- * Obtain session lock
- * @param int $rowid id of the row with session record
- * @param int $timeout max allowed time to wait for the lock in seconds
- * @return bool success
- */
- public function get_session_lock($rowid, $timeout) {
- // NOTE: there is a potential locking problem for database running
- // multiple instances of moodle, we could try to use pg_advisory_lock(int, int),
- // luckily there is not a big chance that they would collide
- if (!$this->session_lock_supported()) {
- return;
- }
- parent::get_session_lock($rowid, $timeout);
- $timeoutmilli = $timeout * 1000;
- $sql = "SET statement_timeout TO $timeoutmilli";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result) {
- pg_free_result($result);
- }
- $sql = "SELECT pg_advisory_lock($rowid)";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $start = time();
- $result = pg_query($this->pgsql, $sql);
- $end = time();
- try {
- $this->query_end($result);
- } catch (dml_exception $ex) {
- if ($end - $start >= $timeout) {
- throw new dml_sessionwait_exception();
- } else {
- throw $ex;
- }
- }
- if ($result) {
- pg_free_result($result);
- }
- $sql = "SET statement_timeout TO DEFAULT";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result) {
- pg_free_result($result);
- }
- }
- public function release_session_lock($rowid) {
- if (!$this->session_lock_supported()) {
- return;
- }
- if (!$this->used_for_db_sessions) {
- return;
- }
- parent::release_session_lock($rowid);
- $sql = "SELECT pg_advisory_unlock($rowid)";
- $this->query_start($sql, null, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- if ($result) {
- pg_free_result($result);
- }
- }
- /**
- * Driver specific start of real database transaction,
- * this can not be used directly in code.
- * @return void
- */
- protected function begin_transaction() {
- $this->savepointpresent = true;
- $sql = "BEGIN ISOLATION LEVEL READ COMMITTED; SAVEPOINT moodle_pg_savepoint";
- $this->query_start($sql, NULL, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- pg_free_result($result);
- }
- /**
- * Driver specific commit of real database transaction,
- * this can not be used directly in code.
- * @return void
- */
- protected function commit_transaction() {
- $this->savepointpresent = false;
- $sql = "RELEASE SAVEPOINT moodle_pg_savepoint; COMMIT";
- $this->query_start($sql, NULL, SQL_QUERY_AUX);
- $result = pg_query($this->pgsql, $sql);
- $this->query_end($result);
- pg_free_result($result);
- }
- /**
- * Driver specific abort of real database transaction,
- * this can not be used directly in code.
- * @return void
- */
- protected functi